import os
import re
import sys
import time
from datetime import datetime


def sum_num(a,b):
    return a+b
# 求两个数的最大值
def max_num(a,b):
    return max(a,b)



print(__name__)  #   所有模块当中自带main   __main__
# time.sleep(3)
print(os.path.dirname(__file__))   #动态的绝对路径

print(datetime.now())

print(re.sub(r'[^0-9]', '', '1b2qfqewc3ef2'))

print(sys)